1. Field of the Invention
The present invention relates to image processing method and apparatus at the time when images recorded on an original such as a photographic print, a photographic film, or the like, are converted to image data by an image input device such as a scanner.
2. Description of the Related Art
Conventionally, in an exposure system in a silver salt photographic technology, printing is generally effected by analogue exposure (i.e., surface exposure: an image is exposed onto a photosensitive material with light being irradiated on an entire surface of an original). Namely, a developed negative film is positioned at a predetermined printing position, light from a white light source (i.e., a halogen lamp or the like) is illuminated on the negative film, and a transmission image from the negative film is imaged (exposed) on a photographic printing paper.
In the analogue exposure system like the above, an image of an original recorded on the negative film can be reproduced faithfully.
On the other hand, in recent years, a so-called digital printer has been technologically improved, in which an image of an original is converted to digital data, subjected to predetermined image processing, and exposed onto a photosensitive material so as to obtain a print image. This makes it possible to prepare an image which is substantially equal to that of the silver salt photography.
In the above-described digital exposure processing, the image of the original is read by a scanner, an image density signal of each of colors of the read image is converted to density data in accordance with spectral sensitivity characteristics of a paper on which the image is printed, and for example, by scanning a semiconductor laser beam, the image is recorded.
By digitizing the image of the original in such a way as described above, various incidental operations (size change, character input, and the like) can be easily effected and it is possible to make a contribution to the development in the field of photography.
However, in the digital exposure processing, practically, a transmission image of a negative film is not printed on a photographic printing paper and the image of the original is read by the scanner. In this case, even when a film of a different type is read, there are some elements which do not exhibit any change in respective density signals of the read image.
Namely, gradation, color tone, and the like are not determined based on the kind of negative film, and are largely influenced by a resolution of the scanner or a resolution of the printer. For this reason, so long as some correction is not made, an image cannot be faithfully reproduced.
Further, there exist various kinds of negative films having different grades (soft gradation, medium gradation, hard gradation, hardest gradation, ultra-hard gradation), different photographic sensitivities, contrast, fog, color sensitivities, image qualities (granularity, resolution, sharpness, MTF (modulation transfer function)), and the like. Even when an image is photographed by using the different kinds of negative films described above, there are some elements which do not exhibit any change in respective density signals of an image read by the scanner.
For example, when different colors are photographed by using a film of which color materials have different spectral distributions, there is a possibility that read density signals becomes the same depending upon the spectral distribution of the scanner. Accordingly, when images are printed on the basis of the image density signals, the images are recorded as entirely the same image.
In view of the above-described circumstances, it is an object of the present invention to provide image processing method and apparatus in which, when an image is printed by digital exposure processing on the basis of an image of an original, the image is faithfully reproduced with an element added which does not exhibit any change in image data read at the time of reading the image of the original.
A first aspect of the present invention is an image processing method in which an image of an original is read by an image input device, the read image data is converted to density data used when printing onto a photosensitive material, and an image is obtained on the photosensitive material by digital exposure, wherein, when the image data is converted to the density data used when printing onto the photosensitive material, the image data is corrected on the basis of parameters determined by combinations of print finish characteristics, including at least image input device characteristics, kind of original, kind of photosensitive material, and exposure amount characteristics, which affect a print image when the image of the original is printed onto the photosensitive material by an analogue exposure system.
A second aspect of the present invention is an image processing method in which an image of an original is read by an image input device, the read image data is converted to density data used when printing onto a photosensitive material, and an image is obtained on the photosensitive material by digital exposure, wherein, when the image data is converted to the density data used when printing onto the photosensitive material, on the basis of parameters determined by combinations of print finish characteristics, including at least image input device characteristics, kind of original, kind of photosensitive material, and exposure amount characteristics, which affect a print image when the image of the original is printed onto the photosensitive material by an analogue exposure system, the density data used when printing onto the photosensitive material while correcting the image data, and in order to display the image on a monitor, on the basis of the density data, data for monitor display is generated so that gradation and color tone when printing onto the photosensitive material coincide with appearances of gradation and color tone when displayed on the monitor.
In accordance with the above-described first and second aspects, when, for example, a negative film is used as an original, a transmission image of the negative film is read, and on the basis of the read image data, an image is formed on a photographic printing paper by digital exposure, in order to obtain a finish state which is equal to that when printed onto the photographic printing paper serving as a photosensitive material by a printer of an analogue exposure system, the density data is obtained while the image data is being corrected on the basis of the parameters determined by combinations of print finish characteristics. For this reason, an image finish print in the digital exposure can have an image quality which is equal to that of a finish print obtained by the analogue exposure system.
A third aspect of the present invention is an image processing method according to the first or second aspect, in which the exposure amount characteristics is a characteristic of change in printing density caused by a color filter in the analogue exposure system, and on the basis of exposure amount characteristics, the change in printing density is simulated by calculation.
In accordance with the third aspect of the present invention, usually, in the analogue exposure system, a color filter is disposed in a direction in which light from a light source is illuminated, and an amount of exposure for each color is adjusted. Namely, since an amount of light for each of colors can be adjusted by an amount by which each color filter is inserted, even if exposure processing of a fixed time is effected for each of colors, the amount of exposure on the photosensitive material can be practically adjusted for each of colors.
On the other hand, the digital exposure system has no means for directly adjusting an amount of light for each of colors, such as a color filter, and the change in printing density by the color filter is simulated by calculation. Namely, for example, in the case of image recording using a semiconductor laser, or the like, so long as an output ratio of semiconductor laser which forms respective colors is obtained from the exposure amount characteristics, color adjustment can be performed which is equal to that when the color filter is used.
A fourth aspect of the present invention is an image processing method according to the first or second aspect, in which, when the image input device characteristics and kind of original are inputted or selected, image data correcting parameters previously stored on the basis of combinations of the image input device characteristics and kind of original are read out.
In accordance with the fourth aspect of the present invention, correction parameters of the image data are, for example, stored by LUT (look-up table) or the like, in such a manner as to correspond to a plurality of combinations of image input device characteristics and kinds of original. By inputting or selecting the image input device characteristics and the kind of original to be used next, the correction parameters can be read out.
A fifth aspect of the present invention is an image processing method according to the first or second aspect, in which, when the kind of original and kind of photosensitive material to be emulated are inputted or selected, image data correcting parameters previously stored on the basis of combinations of the kind of original and kind of photosensitive material.
In accordance with the fifth aspect of the present invention, the correction parameters of the image data are, for example, stored by LUT (look-up table) or the like, in such a manner as to correspond to a plurality of combinations of kinds of originals and kinds of photosensitive materials to be emulated. By inputting or selecting the kind of original and the kind of photosensitive material to be used next, the correction parameters can be read out.
A sixth aspect of the present invention is an image processing method according to the first or second aspect, in which in a process in which the image data is converted to the density data, the image data inputted from the image input device is stored as read image data, the density data obtained from the image data is stored as intermediate image data, the data for RGB monitor display is stored as display image data, and these stored data can be read out and updated independently.
In accordance with the sixth aspect of the present invention, the read image data, the intermediate image data, and the display image data which are obtained in the process in which the image data is converted to the density data are respectively stored, and then, can be independently read out and updated. After the read image data, the intermediate image data and the display image data are obtained from the image data once read, when affected by the image input device characteristics, processing after the time of reading the read image data is performed. Further, when not affected by the image input device characteristics, processing after the time of reading the intermediate image data is performed.
As a result, it is not necessary to start processing from a first operation of inputting an image of an original, and it is thereby possible to reduce an operating time.
A seventh aspect of the present invention is an image processing method according to the sixth aspect, in which the image input device includes a first mode which operates for at least determination of an effective image area and setting of an enlargement ratio, a second mode which operates for determination of parameters which is needed for converting the image data to the density data on the basis of some image data, and a third mode which operates to convert all image data to the density data, the first mode reading an image of an original at a low resolution and monochromatically, the second mode reading it at a low resolution and chromatically, and the third mode reading it at a high resolution and chromatically.
In accordance with the seventh aspect of the present invention, the first mode is a mode which is set so as to make coincidence between a readable area in the image input device and an image region of an original. For example, when an image which is of a cabinet size which is a photographic size is inputted by using the image input device which is capable of reading an image to a maximum copy size (i.e., A3), it is determined about which portion (i.e., area) of the image data read by the image input device is employed. Meanwhile, since the enlargement ratio also must be considered, the read image does not necessarily have the same size of that of the image of the original. In this case, since detailed image data is not required and color of the image is not also required, it suffices that the image is inputted at a low resolution and by monochromatic scan.
The second mode is a mode which is set to determine each of parameters necessary for conversion to the density data on the basis of the image data. It is not necessary to perform processing at a high resolution, and it suffices that the parameters are determined from some image data (i.e., a portion of all the image data distributed substantially uniformly, and in the present system, the image data is evaluated by the monitor, and the image data having about 256xc3x97256 to 512xc3x97512 pixels is required for the above number of pixels, 4700xc3x973400). Accordingly, a high-resolution and color-scan processing is performed.
Finally, the third mode is a mode which is set to convert all image data to the density data, and in this case as well, the high-resolution and color-scan processing is performed.
As described above, by altering a scanning form in accordance with each of applications, rapid processing can be achieved.
An eighth aspect of the present invention is an image processing method according to the first or second aspect, in which a portion of an area of a color image inputted by the image input device, including a gray pixel, is displayed in enlargement, and at the same time, one of a plurality of reference gray previously set is selected and displayed, and a color balance amount for each of the inputted pixels is calculated such that a gray pixel within the portion of the area of the color image is finished as a selected reference gray, so that the inputted image data is corrected.
In accordance with the eighth aspect of the present invention, a plurality of reference gray is previously set and stored, and one of them is selected and displayed on the monitor. On the other hand, concurrent display is provided in a state in which some of images inputted by the image input device is enlarged and is compared with the above reference gray. A color balance amount for each of inputted pixels is calculated and corrected so that the gray image within the some image area is finished as the selected reference gray. In this way, the above operation can be performed while the image data and the reference gray are compared with each other on the monitor, and thereby can be effected rapidly and properly.
A ninth aspect of the present invention is an image processing method according to the sixth or seventh aspect, in which a portion of an area of a color image inputted by the image input device, including a gray pixel, is displayed in enlargement, and at the same time, one of a plurality of reference gray previously set is selected and displayed, and a color balance amount for each of the inputted pixels is calculated such that a gray pixel within the portion of the area of the color image is finished as a selected reference gray, so that the inputted image data is corrected.
In accordance with the ninth aspect of the present invention, at the time of reading in the first mode, the density histogram of the image of the original is prepared in the image input device. By setting the dynamic range suitable for the density of the image data on the basis of the density histogram, a proper reading condition can be recognized and reading in the second mode or in the third mode can be performed in a state of highest reading precision such as setting of gradation or the like. Meanwhile, the reading condition means adjustment of a normal reading time, and adjustment of amount of light may also be made as occasion demands.
A tenth aspect of the present invention is an image processing method according to the first or second aspect, in which the parameters obtained by combinations of the print finish characteristics including said image input device characteristics, the kind of original, the kind of photosensitive material, and exposure amount characteristics are independently stored and can be independently edited, the editing including alternation, addition, and deletion.
In the tenth aspect of the present invention, the parameters obtained by combinations of print finish characteristics including the image input device characteristics, the kind of original, the kind of photosensitive material, and the exposure amount characteristics are stored independently as resources. Subsequently, by independently editing the above parameters at the time of setting parameters under a condition similar or proximate to the above, a parameter setting time can be reduced.
An eleventh aspect of the present invention is an image processing method according to the first or second aspect, in which previously-registered kind of original and kind of photosensitive material are displayed on a monitor, and when plural kinds are indicated for any one of an original and a photosensitive material displayed on the monitor, a specified kind of original or photosensitive material is selected and customized, and when there is a single kind of any one of original and photosensitive material previously registered, the single kind is automatically customized.
In accordance with the eleventh aspect of the present invention, the setting procedures of the kind of original and the kind of photosensitive material are provided. When the previously-registered kind of original and kind of photosensitive material are displayed on the monitor and a plurality of the kind of original or photosensitive material is displayed, a specified kind of original or photosensitive material is selected and customized. When a single kind of original or photosensitive material previously registered is displayed, the single kind is automatically customized. As a result, it is possible to easily effect setting of the kind of original and the kind of photosensitive material.
A twelfth aspect of the present invention is an image processing method according to the first or second aspect, in which at least regular size for a photographic print is previously registered as a print image size printed onto the photosensitive material, the number of pixels of the image data is calculated from a size selected from the registered regular size or a size set by inputting numerical values of actual vertical and horizontal dimensions, and from a print output resolution, and a resolution and a reading range at the time of reading the image of the original in said image input device are determined.
In accordance with the twelfth aspect of the present invention, as a print image size to be printed onto a photosensitive material, at least a regular size for a photographic print is previously registered. The number of pixels of the image data can be calculated from the size selected from the registered regular sizes and from the print output resolution, and the resolution and the reading range of the image of the original when read in the image input device can be determined. Meanwhile, for any other sizes than the regular sizes, by numerically inputting actual vertical and horizontal dimensions, the number of pixels of the image data can be calculated from the inputted size and from the print output resolution in the above-described manner.
A thirteenth aspect of the present invention is an image processing method according to the first or second aspect, in which, by displaying, on the monitor, all the images of the original read by the image input device at a desired enlargement ratio with the center of the monitor being set as a reference, and by indexing a print range at the same enlargement ratio in such a manner as to overlap the display images, the indexed print image size and resolution allows calculation of the number of pixels of the image data from the print output resolution, and allows determination of a resolution and a reading range at the time of reading the image of the original in the image input device.
In accordance with the thirteenth aspect of the present invention, the reading image and the print image size, overlapping each other, are displayed on the monitor with the center of the monitor set as a standard. Accordingly, it is possible to recognize the finished state prior to printing, and operating efficiency is thereby improved.
A fourteenth aspect of the present invention is an image processing apparatus comprising: image input means (32) for reading and inputting an image of an original; image data converting means (40) for converting read image data to a surface sequential image format; first correcting means (44) which converts the image data converted by the image data converting means to a luminance signal, and thereafter, to first density data on the basis of the image input means and a characteristic of the image of the original; second correcting means (48) which, after the first density data corrected by the first correcting means is converted to a print exposure amount on the basis of a characteristic of a photosensitive material in which digital exposure processing is effected by the original and the read image data, converts the converted data to second density data used when printing on the photosensitive material; and monitor display data-generating means (50) for monitor display in which the second density data corrected by the second correcting means is converted such that predicted gradation and color tone obtained at the time of analogue exposure on the photosensitive material coincide with those obtained at the time of digital exposure on the photosensitive material and such that appearances of gradation and color tone when displayed on a monitor coincide with those obtained at the time of digital exposure on the photosensitive material, so that monitor display data is generated.
In accordance with the fourteenth aspect of the present invention, an image of an original is inputted by the image input means. The inputted image data is converted to a surface sequential image by the image data converting means. Namely, there is a possibility that, depending upon the kind of image input means, reading processing is performed in a point sequential manner (for example, a scanning device using a semiconductor laser beam), a line sequential manner (for example, so-called slit scanning), and a surface sequential manner (for example, reading by 3CCD color image sensor). Unifying these data allows facilitation of post-processing. Accordingly, by effecting conversion of the image data to the surface sequential image, image processing can be effected for each of colors in the same way as in the analogue exposure system.
The image data converted to the surface sequential image is converted to a linear luminance signal by the first correcting means, and on the basis of combination of spectral sensitivity distribution characteristics of the original-inputting means and the spectral distribution of the original, a coefficient is determined which converts the luminance value of the above luminance signal to a standard luminance value which can be converted by a previously-standardized density value converting means. On the basis of the determined coefficient, the above luminance signal is converted to the first density data.
In the second correcting means, the first density data corrected by the first correcting means is converted to the exposure amount having color tone and gradation based on the combination of the spectral distribution of the original and the spectral sensitivity distribution of the photosensitive material, and the first density data is converted to the second density data on the photosensitive material on the basis of the above exposure amount.
The second density data corrected by the second correcting means is used to generate, by the monitor display data-generating means, RGB monitor display data which coincides with the print density and color onto the photosensitive material.
When the read image data is printed on the basis of the second density data by the data conversion (correction) process, the image data is printed so as to have gradation and color tone which are equal to those when printed by the analogue exposure system. For example, differences in grade (soft gradation, medium gradation, hard gradation, hardest gradation, ultra-hard gradation), photographic sensitivity, contrast, fog, color sensitivity, image quality (granularity, resolution, sharpness, MTF), and the like, which can be conventionally obtained only by the analogue exposure system when the image on the negative film is printed, can be reproduced by the digital exposure (i.e., by using digital image).
On the other hand, when the spectral sensitivity distribution of the image input device or the spectral distribution of the original (for example, a film) is not known, a chart original photographed by proper exposure may be read by the image input device or a measuring device such as densitometer, and converted to the luminance value. Further, it suffices that setting of the above coefficient is effected by using a least squared method or the like.
A fifteenth aspect of the present invention is an image data output method in which, when previously-stored image data to be outputted is specified and transferred to a print output device, a format necessary for printing in the print output device is set and transferred together with the image data, wherein a plurality of kinds of image data to be outputted can be selected and a plurality of kinds of print size for an identical image data can be inputted or selected.
In accordance with the fifteenth aspect of the present invention, when a print is outputted by the print output device, a plurality of image data are selected, and a plurality of kinds of print size can be specified (inputted or selected) for each of the image data. For this reason, information about desired image data and the size thereof is transferred together without waiting until each image print processing is completed. Accordingly, processing efficiency is achieved.
A sixteenth aspect of the present invention is an image data output method according to the fifteenth aspect, in which the image data is stored in such a manner as to be converted to color information when printed on a predetermined photosensitive material, and the color information is obtained by correcting the image data on the basis of parameters determined by combinations of print finish characteristics including at least image input device characteristics, kind of original, kind of photosensitive material, and exposure amount characteristics, which affect a print image when an image of an original is printed onto a photosensitive material by an analogue exposure system.
In accordance with the sixteenth aspect of the present invention, since the specified image data is color information corrected on the basis of the parameters determined by combinations of print finish characteristics, the finished state which is substantially equal to a print obtained by the analogue exposure system can be obtained.
A seventeenth aspect of the present invention is an image data output device in which image data is transferred to a print output device and a format necessary for printing in the print output device is set and transferred together with the image data, comprising: image data storing means for storing a plurality of image data to be outputted; specifying means which specifies desired image data from the image data storing means; print-size setting means which performs one of selecting a print size for each of the image data specified by the specifying means and inputting an actual print size in the print output device; number-of-print setting means which performs one of input and selection of the number of prints for each of the image data specified by the specifying means; and transferring means for transferring, to the print output device, the image data specified by the specifying means, and the print size and number of prints which correspond to the image data.
In accordance with the seventeenth aspect of the present invention, a plurality of kinds of desired image data can be specified by the specifying means and the print size setting means allows setting of a plurality of kinds of print size for each of the specified image data. The plurality of kinds of print size set for each of the plurality of kinds of image data are transferred, together with the number of prints set by the number-of-print setting means, to the print output means by the transferring means. The print output means allows continuous output of set number of prints of the set print size on the basis of the specified image data. As a result, processing efficiency is promoted.
An eighteenth aspect of the present invention is an image data output method according to the seventeenth aspect, in which the image data is stored in the image data storing means in such a manner as to be converted to color information when printed on a predetermined photosensitive material, and the color information is obtained by correcting the image data on the basis of parameters determined by combinations of print finish characteristics including at least image input device characteristics, kind of original, kind of photosensitive material, and exposure amount characteristics, which affect a print image when an image of an original is printed onto a photosensitive material by an analogue exposure system.
In accordance with the eighteenth aspect of the present invention, since the specified image data is color information which is corrected on the basis of the parameters determined by the combinations of print finish characteristics, a finished state which is substantially equal to a print obtained by the analogue exposure system can be obtained.
A nineteenth aspect of the present invention is an image data output method according to the fifteenth aspect, in which, when printing is performed by using at least one print size specified or selected from the plurality of print sizes, layout information is added so that automatic layout is performed on the basis of a size of photosensitive material loaded in the print output device and the format and the image data are transferred to the print output device.
In accordance with the nineteenth aspect of the present invention, the size of a photosensitive material loaded in the print output device is usually relatively large. For this reason, when the photosensitive material is printed irrespective of the set image size, there is a possibility that a blank space becomes large or a portion of the image is not printed. Accordingly, automatic layout is made on the basis of the size of the photosensitive material load in the print output device, and the layout information is transferred to the print output device together with the format and the image data. As a result, a wasted portion of the photosensitive material is eliminated so that the photosensitive material is used effectively.
A twentieth aspect of the present invention is an image data output method according to the fifteenth aspect, in which, when the print size is not inputted or selected, or when a preceding print size is not proper, a regular size which approximates most closely a size of an image of an original when image data is read from the image of the original is automatically selected.
In accordance with the twentieth aspect of the present invention, for example, when the print size is not inputted or selected, a regular size which is closest to a size when the image data is read from the image of the original is automatically selected, and it is possible to save labor such as resetting or the like.
A twenty-first aspect of the present invention is an image data output method according to the fifteenth aspect, in which, when the inputted or selected print size does not coincide with the size of the image data, enlargement, reduction, or trimming of the image data is performed, so that the image data is automatically altered to the inputted or selected print size.
In accordance with the twenty-first aspect of the present invention, when, for example, longitudinal photographic originals and horizontal photographic originals are all inputted as the horizontal image data, and a print of a horizontal size is specified, a print of an image taken from a longitudinal photographic original has blank spaces at left and right sides thereof and respective portions of upper and lower sides of the print are not printed. Accordingly, when the set print size does not coincide with the size of the image data, enlargement, reduction, or trimming of the print size is automatically effected, and at least blank spaces are thereby eliminated. As a result, an appearance of a finished print image is improved.
A twenty-second aspect of the present invention is an image data output method according to the fifteenth aspect, in which, when the image data is color image data, designation of the image data allows conversion from the color image data to monochromatic image data, and when each one is selected from a plurality of gray balance and a plurality of gradation, the color image data is converted to the monochromatic image data on the basis of the selected gray balance and gradation.
In accordance with the twenty-second aspect of the present invention, the color image data can be printed as a monochromatic image. In this case, when each one is selected from a plurality of set gray balance and a plurality of set gradation, the color image data is converted to monochromatic image data on the basis of the selected gray balance and gradation. As a result, an unnatural state of gradation, biasing of gray balance, or the like, which is caused when the color image is changed to the monochromatic image without the gray balance and gradation being based, is prevented, and the monochromatic image is printed so as to have a gradation which is substantially equal to that of a print of the color image.
A twenty-third aspect of the present invention is an image data output method according to the fifteenth aspect, in which presence or absence of a white border in a peripheral portion of the image can be selected when output of prints is performed in the print output device, and when presence of the white border is selected, an index indicating a white border region is printed together with the image, and at the time of printing the index, a character or a mark which specifies the image data is printed.
In accordance with the twenty-third aspect of the present invention, various photosensitive materials are used to perform printing. For this reason, when a white border is formed, there is a possibility that the region of the white border is not clear. Accordingly, an index indicating the white border region is added at the time of image printing, and further, the image data is specified by characters or symbols within the white border region. As a result, when the image can be cut off with the index used as a mark, and an image of a desired size (having the white border) is thereby obtained. Further, since the image with the white border has characters, symbols, or the like, which specify the image data, printed in the white border region, this is convenient for sorting of prints.
Meanwhile, when, as means for sorting images having no white border, a perforation or the like is formed which allows easy cutting of a boundary line between the image and a white border portion which is provided in only a lower side of the image in the vertical direction, the white border portion can easily be eliminated at the time of print sorting.
A twenty-fourth aspect of the present invention is an image data output method according to the above twenty-third aspect, in which layout is automatically set so that the white border region and a non-print region to be formed in a peripheral portion of a photosensitive material in the print output device overlap with each other.
The photosensitive material used in the print output device is constructed in that the entire region thereof is not used as a region in which images can be recorded and a non-image region is provided in a peripheral portion thereof, and a so-called wasted portion exists thereon. However, in the case of an image which requires the white border region, the above non-image portion has the same function as that of the white border. Accordingly, when layout is automatically set such that the white border region and the non-print region formed in the peripheral portion of the photosensitive material overlap each other, the wasted portion of the photosensitive material is effectively utilized.